feat(types): remove Gas Town types from core built-in types

Core beads built-in types now only include work types:
- bug, feature, task, epic, chore

Gas Town types (molecule, gate, convoy, merge-request, slot, agent,
role, rig, event, message) are now "well-known custom types":
- Constants still exist for code convenience
- Require types.custom configuration for validation
- bd types command shows core types and configured custom types

Changes:
- types.go: Separate core work types from well-known custom types
- IsValid(): Only accepts core work types
- bd types: Updated to show core types and custom types from config
- memory.go: Use ValidateWithCustom for custom type support
- multirepo.go: Only check core types as built-in
- Updated all tests to configure custom types

This allows Gas Town (and other projects) to define their own types
via config while keeping beads core focused on work tracking.

Closes: bd-find4

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

internal/molecules/molecules_test.go

@@ -81,6 +81,11 @@ func TestLoader_LoadAll(t *testing.T) {
 		t.Fatalf("Failed to set prefix: %v", err)
 	}
 
+	// Configure custom types for Gas Town types (bd-find4)
+	if err := store.SetConfig(ctx, "types.custom", "molecule"); err != nil {
+		t.Fatalf("Failed to set types.custom: %v", err)
+	}
+
 	// Create a project-level molecules.jsonl
 	moleculesPath := filepath.Join(beadsDir, "molecules.jsonl")
 	content := `{"id":"mol-feature","title":"Feature Template","issue_type":"molecule","status":"open","description":"Standard feature workflow"}
@@ -150,6 +155,11 @@ func TestLoader_SkipExistingMolecules(t *testing.T) {
 		t.Fatalf("Failed to set prefix: %v", err)
 	}
 
+	// Configure custom types for Gas Town types (bd-find4)
+	if err := store.SetConfig(ctx, "types.custom", "molecule"); err != nil {
+		t.Fatalf("Failed to set types.custom: %v", err)
+	}
+
 	// Pre-create a molecule in the database (skip prefix validation for mol-* IDs)
 	existingMol := &types.Issue{
 		ID:         "mol-existing",

internal/rpc/rpc_test.go

@@ -51,6 +51,13 @@ func setupTestServer(t *testing.T) (*Server, *Client, func()) {
 		t.Fatalf("Failed to set issue_prefix: %v", err)
 	}
 
+	// Configure Gas Town custom types for test compatibility (bd-find4)
+	if err := store.SetConfig(ctx, "types.custom", "molecule,gate,convoy,merge-request,slot,agent,role,rig,event,message"); err != nil {
+		store.Close()
+		os.RemoveAll(tmpDir)
+		t.Fatalf("Failed to set types.custom: %v", err)
+	}
+
 	server := NewServer(socketPath, store, tmpDir, dbPath)
 
 	ctx, cancel := context.WithCancel(context.Background())

internal/storage/memory/memory.go

@@ -190,8 +190,17 @@ func (m *MemoryStorage) CreateIssue(ctx context.Context, issue *types.Issue, act
 	m.mu.Lock()
 	defer m.mu.Unlock()
 
-	// Validate
-	if err := issue.Validate(); err != nil {
+	// Get custom types and statuses for validation
+	var customTypes, customStatuses []string
+	if typeStr := m.config["types.custom"]; typeStr != "" {
+		customTypes = parseCustomStatuses(typeStr)
+	}
+	if statusStr := m.config["status.custom"]; statusStr != "" {
+		customStatuses = parseCustomStatuses(statusStr)
+	}
+
+	// Validate with custom types
+	if err := issue.ValidateWithCustom(customStatuses, customTypes); err != nil {
 		return fmt.Errorf("validation failed: %w", err)
 	}
 
@@ -243,9 +252,18 @@ func (m *MemoryStorage) CreateIssues(ctx context.Context, issues []*types.Issue,
 	m.mu.Lock()
 	defer m.mu.Unlock()
 
+	// Get custom types and statuses for validation
+	var customTypes, customStatuses []string
+	if typeStr := m.config["types.custom"]; typeStr != "" {
+		customTypes = parseCustomStatuses(typeStr)
+	}
+	if statusStr := m.config["status.custom"]; statusStr != "" {
+		customStatuses = parseCustomStatuses(statusStr)
+	}
+
 	// Validate all first
 	for i, issue := range issues {
-		if err := issue.Validate(); err != nil {
+		if err := issue.ValidateWithCustom(customStatuses, customTypes); err != nil {
 			return fmt.Errorf("validation failed for issue %d: %w", i, err)
 		}
 	}

internal/storage/memory/memory_test.go

@@ -21,6 +21,12 @@ func setupTestMemory(t *testing.T) *MemoryStorage {
 		t.Fatalf("failed to set issue_prefix: %v", err)
 	}
 
+	// Configure Gas Town custom types for test compatibility (bd-find4)
+	// These types are no longer built-in but many tests use them
+	if err := store.SetConfig(ctx, "types.custom", "message,merge-request,molecule,gate,agent,role,rig,convoy,event,slot"); err != nil {
+		t.Fatalf("failed to set types.custom: %v", err)
+	}
+
 	return store
 }
 

internal/storage/sqlite/gate_no_daemon_test.go

@@ -29,6 +29,11 @@ func TestGateFieldsPreservedAcrossConnections(t *testing.T) {
 		t.Fatalf("failed to set issue_prefix: %v", err)
 	}
 
+	// Configure custom types for Gas Town types (gate is not a core type)
+	if err := store1.SetConfig(ctx, "types.custom", "gate"); err != nil {
+		t.Fatalf("failed to set types.custom: %v", err)
+	}
+
 	gate := &types.Issue{
 		ID:        "beads-test1",
 		Title:     "Test Gate",

internal/storage/sqlite/sqlite_test.go

@@ -39,6 +39,14 @@ func setupTestDB(t *testing.T) (*SQLiteStorage, func()) {
 		t.Fatalf("failed to set issue_prefix: %v", err)
 	}
 
+	// Configure Gas Town custom types for test compatibility (bd-find4)
+	// These types are no longer built-in but many tests use them
+	if err := store.SetConfig(ctx, "types.custom", "message,merge-request,molecule,gate,agent,role,rig,convoy,event,slot"); err != nil {
+		store.Close()
+		os.RemoveAll(tmpDir)
+		t.Fatalf("failed to set types.custom: %v", err)
+	}
+
 	cleanup := func() {
 		store.Close()
 		os.RemoveAll(tmpDir)

internal/types/types.go

@@ -476,13 +476,20 @@ func (s Status) IsValidWithCustom(customStatuses []string) bool {
 // IssueType categorizes the kind of work
 type IssueType string
 
-// Issue type constants
+// Core work type constants - these are the built-in types that beads validates.
+// All other types require configuration via types.custom in config.yaml.
+const (
+	TypeBug     IssueType = "bug"
+	TypeFeature IssueType = "feature"
+	TypeTask    IssueType = "task"
+	TypeEpic    IssueType = "epic"
+	TypeChore   IssueType = "chore"
+)
+
+// Well-known custom types - constants for code convenience.
+// These are NOT built-in types and require types.custom configuration for validation.
+// Used by Gas Town and other infrastructure that extends beads.
 const (
-	TypeBug          IssueType = "bug"
-	TypeFeature      IssueType = "feature"
-	TypeTask         IssueType = "task"
-	TypeEpic         IssueType = "epic"
-	TypeChore        IssueType = "chore"
 	TypeMessage      IssueType = "message"       // Ephemeral communication between workers
 	TypeMergeRequest IssueType = "merge-request" // Merge queue entry for refinery processing
 	TypeMolecule     IssueType = "molecule"      // Template molecule for issue hierarchies
@@ -495,10 +502,12 @@ const (
 	TypeSlot         IssueType = "slot"          // Exclusive access slot (merge-slot gate)
 )
 
-// IsValid checks if the issue type value is valid
+// IsValid checks if the issue type is a core work type.
+// Only core work types (bug, feature, task, epic, chore) are built-in.
+// Other types (molecule, gate, convoy, etc.) require types.custom configuration.
 func (t IssueType) IsValid() bool {
 	switch t {
-	case TypeBug, TypeFeature, TypeTask, TypeEpic, TypeChore, TypeMessage, TypeMergeRequest, TypeMolecule, TypeGate, TypeAgent, TypeRole, TypeRig, TypeConvoy, TypeEvent, TypeSlot:
+	case TypeBug, TypeFeature, TypeTask, TypeEpic, TypeChore:
 		return true
 	}
 	return false
@@ -569,8 +578,7 @@ func (t IssueType) RequiredSections() []RequiredSection {
 			{Heading: "## Success Criteria", Hint: "Define high-level success criteria"},
 		}
 	default:
-		// Chore, message, molecule, gate, agent, role, convoy, event, merge-request
-		// have no required sections
+		// Chore and custom types have no required sections
 		return nil
 	}
 }

internal/types/types_test.go

@@ -539,20 +539,24 @@ func TestIssueTypeIsValid(t *testing.T) {
 		issueType IssueType
 		valid     bool
 	}{
+		// Core work types are always valid
 		{TypeBug, true},
 		{TypeFeature, true},
 		{TypeTask, true},
 		{TypeEpic, true},
 		{TypeChore, true},
-		{TypeMessage, true},
-		{TypeMergeRequest, true},
-		{TypeMolecule, true},
-		{TypeGate, true},
-		{TypeAgent, true},
-		{TypeRole, true},
-		{TypeConvoy, true},
-		{TypeEvent, true},
-		{TypeSlot, true},
+		// Gas Town types require types.custom configuration
+		{TypeMessage, false},
+		{TypeMergeRequest, false},
+		{TypeMolecule, false},
+		{TypeGate, false},
+		{TypeAgent, false},
+		{TypeRole, false},
+		{TypeConvoy, false},
+		{TypeEvent, false},
+		{TypeSlot, false},
+		{TypeRig, false},
+		// Invalid types
 		{IssueType("invalid"), false},
 		{IssueType(""), false},
 	}

internal/validation/bead_test.go

@@ -211,19 +211,18 @@ func TestParseIssueType(t *testing.T) {
 		wantError    bool
 		errorContains string
 	}{
-		// Valid issue types
+		// Core work types (always valid)
 		{"bug type", "bug", types.TypeBug, false, ""},
 		{"feature type", "feature", types.TypeFeature, false, ""},
 		{"task type", "task", types.TypeTask, false, ""},
 		{"epic type", "epic", types.TypeEpic, false, ""},
 		{"chore type", "chore", types.TypeChore, false, ""},
-		{"merge-request type", "merge-request", types.TypeMergeRequest, false, ""},
-		{"molecule type", "molecule", types.TypeMolecule, false, ""},
-		{"gate type", "gate", types.TypeGate, false, ""},
-		{"event type", "event", types.TypeEvent, false, ""},
-		{"message type", "message", types.TypeMessage, false, ""},
-		// Gas Town types (agent, role, rig, convoy, slot) have been removed
-		// They now require custom type configuration,
+		// Gas Town types require types.custom configuration (invalid without config)
+		{"merge-request type", "merge-request", types.TypeTask, true, "invalid issue type"},
+		{"molecule type", "molecule", types.TypeTask, true, "invalid issue type"},
+		{"gate type", "gate", types.TypeTask, true, "invalid issue type"},
+		{"event type", "event", types.TypeTask, true, "invalid issue type"},
+		{"message type", "message", types.TypeTask, true, "invalid issue type"},
 
 		// Case sensitivity (function is case-sensitive)
 		{"uppercase bug", "BUG", types.TypeTask, true, "invalid issue type"},